Non-Class 125 VDC Control Power (NK) Flashcards
How many hours of battery power will NK provide on a loss of station AC power?
2 hours at full loading
what is the design basis for NK?
Provide sufficient power for the protection and control of transformers, switchgear, and the digital
fault recorder.
NK provides normal power source to plant computer (NQ) through what
inverter
What are the M45 loads?
plant computer
NKN-D41, D42, D43
Main Generator primary and backup tripping circuits
What is powered from NKN-D41?
Switchgear control power for NAN-S01/ S03, Main Generator Auxiliaries, Turbine Building HVAC
What is powered from NKN-D42?
Switchgear control power for NAN-S02/ S04
Radwaste annunciators
Motor Operated Disconnects
Plant annunciators
What is powered from NKN-D43?
Oscillograph
turbine protection
transformer annunciators
plant annunciators
Normal control power for NAN-S05/S06?
M45 -> U45
M46 -> U46
What are the NKN-M46 loads?
NKN-D44
NKN-D45
emergency pumps for:
Main Turbine
main generator
MFPT oil pump motors
containment personnel airlocks
Where are the NK battery breakers normally operated from?
control room
can be done locally
What relays/alarms exist for NK busses?
bus undervoltage
soft/hard ground
How many fans are in the NK battery room and why are they important?
2 100% capacity exhaust fans in battery room
Prevent buildup of potentially explosive hydrogen levels
What is the purpose of NKN-D19?
cooling tower fan load center control power
How do you read the amp indications in the CR for NK batteries?
Amps to left (Battery charging)
Amps to right (Battery discharging)
Are NK battery chargers make before break or the opposite?
normally make before break but can do either one
What is provided to ensure the 120VAC UPS D-Panel, NQN-D01 remains energized on a loss of NKN-M45?
static transfer switch connected to a voltage regulator getting power directly from an MCC (M08)
What is powered by NKN-D44?
RCP breaker controlW
What is powered from NKN-D45?
SSO Cabinet (SSR room)
What could bring in this alarm?
NKN-M45 Bus under voltage, ground, or breaker trip
Battery Charger E/EI overvoltage, undervoltage,
reverse current, AC supply undervoltage or charger
failure
What could bring in this alarm?
NKN-M46 Bus under voltage, ground, or breaker trip
Battery Charger F/EF overvoltage, undervoltage,
reverses current, AC supply under voltage or charger
failure
What could bring in this alarm?
NKN-D41/42/43 Bus under voltage, ground, or
breaker overload trip
What could bring in this alarm?
NKN-D19 Bus under voltage, ground, or breaker trip
Battery Charger G overvoltage, under voltage,
reverse current, AC supply under voltage or charger
failure
